Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Population Control”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 73 records · Page 4Linked to original sources
PubMedDate not supplied

Lymphedema and bladder-emptying difficulties after radical hysterectomy for early cervical cancer and among population controls.

The aim of the study was to acquire knowledge that can be used to refine radical hysterectomy to improve quality-of-life outcome. Data were collected in 1996-1997 by means of an anonymous postal questionnaire in a follow-up study of two cohorts (patients and population controls). We attempted to enroll all 332 patients with stage IB-IIA cervical cancer registered in 1991-1992 at the seven departments of gynecological oncology in Sweden and 489 population controls. Ninety three (37%) of the 256 women with a history of cervical cancer who answered the questionnaire (77%) were treated with surgery alone. Three-hundred fifty population controls answered the questionnaire (72%). Women treated with radical hysterectomy, as compared with controls, had an 8-fold increase in symptoms indicating lymphedema (25% reported distress due to lymphedema), a nearly 9-fold increase in difficult emptying of the bladder, and a 22-fold increase in the need to strain to initiate bladder evacuation. Ninety percent of the patients were not willing to trade off survival for freedom from symptoms. Avoiding to induce long-term lymphedema or bladder-emptying difficulties would probably improve quality of life after radical hysterectomy (to cure cervical cancer). Few women want to compromise survival to avoid long-term symptoms.

Adult↗
PubMed1990

[Survival and causes of secondary mortality in patients undergoing coronary bypass. Comparison with a same age control population].

During 10 years, 867 patients in whom the same surgical team had performed coronary bypass were followed up regularly without any of them being lost sight of. Moreover, the cause of all deaths in this group could be determined fairly accurately. A comparison of mortality between these patients and an age-matched control population studied longitudinally, year after year, showed that the mortality rate in the surgical group was slightly higher than in the control group (84 vs 77). Conversely, when the operative mortality was discounted, it appeared that the patients who survived coronary bypass had a much better survival than the control population (47 vs 77). Without any doubt, the prognosis for life is improved by surgery. In particular, patients with three-vessel disease (58 per cent), tight stenosis of the common coronary artery (10-25 per cent) or altered ventricular ejection fraction (about 30 per cent) would probably have died without myocardial revascularization. However, this study produced a rather astonishing result: compared with the control population, the decrease of long-term mortality in patients who survived coronary bypass was due not only to the decrease of cardiovascular deaths (16 vs 24) but also of deaths due to cancer (15 vs 27) or to other causes (16 vs 26). This suggests that a more hygienic life and a correct medical follow-up contribute to a large extent to the long-term survival of these surgical patients.

Actuarial Analysis↗
PubMed1990

Optimal population control with uncertain output.

"This note has shown how the techniques of stochastic control theory can be used to analyze the impact of uncertainty about non-labour inputs on optimal population control expenditure. While we have chosen very simple structure, it has allowed us to isolate the channels through which uncertainty affects the optimal plan, in this case causing expected expenditure on control to rise more slowly or fall more rapidly than its deterministic counterpart. Given the long-term implications of changes in population growth at any instant, and the stochastic nature of the environment in which control decisions are made, it is likely that useful insights could be obtained by extending the stochastic control approach to more complicated population control structures."

Demography↗
PubMed2002

No increased frequency of malignant neoplasms in polymyalgia rheumatica and temporal arteritis. A prospective longitudinal study of 398 cases and matched population controls.

OBJECTIVE: To determine the prevalence and incidence of cancer in patients with polymyalgia rheumatica (PMR) and temporal arteritis (TA) compared to matched population controls. METHODS: In a population based study 1987-97, 398 patients were diagnosed with PMR or TA. Each patient was randomly assigned 4 age and sex matched controls from the same county, totaling 1592 controls. All patients and controls were cross-checked with data files at the Cancer Registry of Norway, for cancers registered up to the end of 1998. RESULTS: Prior to inclusion, cancer was diagnosed in 32 patients with PMR or TA (8.0%) and 153 controls (9.6%) (OR 0.82, 95% CI 0.55-1.22, p = 0.3). After inclusion, malignant neoplasms were discovered in 34 patients with PMR or TA (9.3%) compared to 143 controls (10.8%) (relative risk 0.86, 95% CI 0.59-1.26, p = 0.4). Thus there was no difference between patients with PMR or TA and their controls regarding prevalence or incidence of cancer. The interval between inclusion and the time of diagnosis of malignant neoplasm did not differ between patients and controls. No significant difference in types or localization of malignant neoplasms was found in patients compared to controls. CONCLUSION: No differences were found in frequencies or types of malignant neoplasms between patients with PMR or TA and population controls. Neither PMR nor TA as defined by present diagnostic criteria appears associated with cancer.

Giant Cell Arteritis↗
PubMed1977

Parallel studies of HLA antigens in patients with rheumatic heart disease and scleritis: comparisons with three control populations.

Parallel studies were carried out on HLA antigens in patients with rheumatic heart disease and scleritis. Comparison with one control population showed a significant excess of BW15 in both disease samples, while a comparison with two other control populations, showed the excess not to be significant. Possible reasons for this discrepancy are discussed, together with the effect on statistical significance of a small percentage of false antigen assignments in one of the samples. A small systematic serological false assignment of an antigen can, by itself, produce a significant result more easily if the frequency of the antigen being detected is low than if it is high. It is suggested that this effect may contribute to the discrepant significant results obtained by different workers in some HLA and disease studies.

Eye Diseases↗
PubMed1976

Casual, basal and supplemental blood pressures in 519 first-degree relatives of substantial hypertensive patients and in 350 population controls.

1. The casual blood pressure is the sum of the relatively stable basal pressure taken under defined conditions of rest and the labile supplemental pressure (casual minus basal), which represents the response to the current degree of physical, mental and probably metabolic stimulation. 2. The basal and supplemental blood pressures behave differently and it seems likely that different factors are involved in their pathogenesis. 3. The 5 and 8 years follow-up mortality is closely related to the basal pressure but not to the supplemental pressure. 4. The rise with age in the basal blood pressure is greater in the relatives of substantial hypertensive patients than in population control subjects. 5. Above the age group 30-39 years there is an increase in the rate of rise of the mean basal blood pressure with age among the first-degree relatives of hypertensive patients. In a population control group an acceleration in the rate of rise of the mean basal blood pressure with age also occurs but a decade or more later than in the relatives of hypertensive patients. 6. In males the mean supplemental pressures (systolic and diastolic) do not rise appreciably with age and the mean supplemental pressures of first-degree relatives and control subjects do not differ appreciably. 7. In females the mean supplemental pressures rise with age but, except after age 60 years, the pressure rise in first-degree relatives is only a little greater than in control subjects. 8. When hypertensive patients with similar casual blood pressures are compared the basal blood pressures are higher in patients with glomerulonephritis than in essential hypertensive patients. 9. In the first-degree relatives of substantial hypertensive patients high-ranking basal blood pressures occur much more frequently than in general population control subjects. 10. The close resemblance of the blood pressures in like twins indicates that genetic or familial factors have an important influence on blood pressure, and on the occurrence of frank hypertension.

Adolescent↗
PubMed1993

Effectiveness of the Waksberg telephone sampling method for the selection of population controls.

The effectiveness of the Waksberg telephone sampling method and practical aspects of its implementation were evaluated during the selection of control subjects for a population-based case-control study conducted in Maryland, Virginia, West Virginia, and Washington, DC, in 1991. The first stage of the two-stage sampling procedure was equivalent to simple random sampling. Each telephone number selected was dialed up to 13 times to establish the type of connection. Residential connections were used to generate additional telephone numbers in the second stage by changing the last two digits. Overall, 3,860 telephone numbers yielded 1,311 residences. The proportion of residences was higher in the second stage (54%) than in the first (11%), while that of numbers "not in service" was lower (12% vs. 67%, respectively). Fewer calls (8,735) were made than would have been required by a simple random sampling procedure (up to 18,522). The geographic distribution of residences was similar at both stages of sampling. At the end of enrollment, each sampling unit had yielded 9.8 residences, but only 64% reached 9-11 residences. Compliance rates were 96% for screening (1,259 of 1,311 residences), 90% for interviewing (362 of 403), and 86% overall. Relative to simple random sampling, the Waksberg method considerably reduced the total number of telephone calls, but the sampling process was more complex to manage. This method is particularly suitable for selecting population controls when the density of residential connections is low and variables of interest are not homogeneous within sampling units. Random digit dialing remains an effective method for selecting population controls.

Data Collection↗
PubMed1972

Pakistan to expand population control.

The President of Pakistan, Mr. Bhutto, made the statement during a recent press interview that his government will expand activities in the field of family planning and population control. According to President Bhutto there is no formal opposition to family planning in the teachings of the Moslem religion or in the Koran. The economic state of the country and the rapid growth of population make control measures a necessity.

Asia↗
PubMed1994

Repackaging population control.

"While the abortion controversy captured the world's headlines, the real significance of the UN's [1994 International Conference on Population and Development] went largely unnoticed.... After decades of failure, the UN has finally pushed the issue of population control center stage by repackaging it in a blurry concern for the rights of women." The author argues that the conference's strategy was to target women as both the cause of overpopulation and the locus of the problem's solution.

Communication↗
PubMed1995

[Adaptation to effort in patients with chronic cardiac insufficiency; study by post-exercise Doppler echocardiography, comparative results with a control population].

Adaptation to exercise was studied by post-exercise Doppler echocardiography in patients with chronic cardiac failure and an apparently healthy control population matched for age. This post-exercise Doppler echocardiographic method initially introduced for the detection of myocardial ischaemia has already been validated in normal subjects for the analysis of haemodynamic changes caused by exercise providing the data is recorded in the first 5 minutes following recovery in the recumbent position. Eleven patients with chronic cardiac failure in NYHA classes II or III with a mean age of 54 +/- 11 years and 6 controls (mean age: 46 +/- 9 years) were investigated. The patients had been stabilised for at least 3 months with a vasodilator and diuretic therapy: the control subjects had no medication. After bicycle ergometry performed to 70% of maximum capacity, the subjects were positioned in the left lateral recumbent position. Doppler echocardiography was then performed in the immediate recovery phase. When compared to the control population, the patients with cardiac failure had a reduced chronotropic reserve, a smaller increase in the parameters of myocardial contractility (maximal aortic velocity, maximal aortic acceleration and left ventricular fractional shortening) without an increase in left ventricular end diastolic dimensions in subjects with severe dilatation under basal conditions (left ventricular end diastolic dimension 69 +/- 3 mm). This result suggests the absence of a Frank-Starling effect. The lack of adaptation of the peripheral vascular system was demonstrated by the lack of reduction of left ventricular end systolic stress, already greatly increased at rest (176 vs 77 +/- 10 g/cm2 for patients, compared with controls; p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adaptation, Physiological↗
PubMed2006

A prospective survey to compare the suitability profiles of over-the-counter ibuprofen and paracetamol use in a French general practitioner-controlled population.

BACKGROUND AND OBJECTIVES: The PAIN (Paracetamol, Aspirin and Ibuprofen New tolerability) study published in 1999 assessed the tolerability of over-the- counter (OTC) analgesics in a French general practitioner (GP)-controlled population and found no apparent difference between the tolerability of ibuprofen and paracetamol (acetaminophen). However, patient selection in that study could cast doubt over the relevance of the results to a more generalised OTC population. The aim of our survey was to prospectively determine what proportion of a French GP-controlled population is able to take ibuprofen and paracetamol in order to allow appropriate interpretation of the PAIN study. METHODS: This was a prospective survey to identify all contraindications/warnings on product labelling for ibuprofen and paracetamol in 5000 patients aged 18-75 years. 100 French GPs each collected anonymised data on 50 patients over a 1-week period using a standardised form. GPs were stratified by geographical location and size of practice. Demographic data for patients were summarised. Contraindications/warnings for ibuprofen and paracetamol were summarised overall and by individual criterion. RESULTS: The mean age of patients was 45.8 (+/- 16.5) years; 42% were males and 58% females. Of these patients, 49.9% would have been ineligible for the PAIN study because of at least one contraindication/warning for ibuprofen, whereas only 6.8% would have been ineligible because of at least one contraindication/warning for paracetamol. More specifically, contraindications to use of ibuprofen was noted in 12.3% of patients and 37.6% of patients should have consulted a doctor before use of this drug. In contrast, contraindications to use of paracetamol were noted in only 0.7% of patients and only 6.1% should have consulted a doctor before use of this drug. CONCLUSIONS: Our survey demonstrates how careful patient selection can limit the generalisability of a study. The PAIN study excluded individuals 'at-risk' from ibuprofen and the tolerability results of this study should therefore be interpreted with extreme caution because the patient population may not be representative of unsupervised OTC analgesic users.

Acetaminophen↗
PubMed2005

Comparison perception of singular transcranial magnetic stimuli by subjectively electrosensitive subjects and general population controls.

Transcranial magnetic stimulation of the dorsolateral prefrontal cortex by single pulses of varying field intensities was used to measure thresholds of individual perception and motor response in three groups of subjects: subjectively electrosensitive people, general population controls with a high burden of complaints related to electromagnetic field (EMF) exposure in the literature (highest decile in complaint burden), and general population controls with a low burden of complaints (lowest decile in complaint burden). The major study endpoint was the ability of the subjects to differentiate between real magnetic stimulation and a sham condition. There were no significant differences between groups in the thresholds, neither of detecting the real magnetic stimulus nor in motor response. But the three groups differed significantly in differentiating between stimulation and sham condition, with the subjectively electrosensitive people having the lowest ability to differentiate and the control group with high level of EMF-related complaints having the best ability to differentiate. Differences between groups were mostly due to false alarm reactions in the sham condition reported by subjectively electrosensitives (SES). We found no objective correlate of the self perception of being "electrosensitive." Overall, our experiment does not support the hypothesis that subjectively electrosensitive patients suffer from a physiological hypersensitivity to EMFs or stimuli. Further research should focus on disposing factors explaining the unspecific sensory hyperresponsiveness of subjectively electrosensitive subjects.

Adolescent↗
PubMedDate not supplied

Estimated change in blood lead concentration in control populations.

Investigators have conducted several studies to assess the effectiveness of lead hazard interventions in reducing children's blood lead levels. For practical and ethical reasons, many of these studies have not included control populations. It is, therefore, impossible for researchers to determine to what extent the reported decline in blood lead concentrations has resulted from intervention versus other factors. In the current retrospective analysis, the authors estimated the change in children's blood lead levels in control populations at 12-mo follow-up. The results suggest that an average 9% decline may be attributed to factors that are unrelated to intervention. Declines of approximately 25% have been reported following several lead-hazard interventions. For these studies, the results of the authors' analysis suggest that approximately 16% of the decline is attributed directly to the intervention.

Age Factors↗
PubMed2000

Serum immunoglobulin G and M concentrations did not appear to be associated with resistance to Pasteurella multocida in a large-bodied turkey line and a randombred control population.

Serum IgG and IgM concentrations in a randombred control line (RBC2) of turkeys and its subline (F), selected long term for increased 16-wk BW were compared. Six-week-old poults were challenged with virulent Pasteurella multocida (1.2 x 10(7) bacteria per bird of serogroup A and serotype 3,4). Sera were collected prior to challenge, and concentrations of IgG and IgM in turkey sera were quantitatively estimated with a Sandwich ELISA using the cross-reactive polyclonal antibodies specific for the chicken Ig isotypes. The F-line turkeys had a higher serum IgM concentration than turkeys from the RBC2 line. There was no significant line difference in IgG concentration. The F line had higher mortality and a shorter number of days to death following challenge with P. multocida than did the RBC2 line. No significant correlation coefficient was found between immunoglobulin isotype concentration in serum and days to death following challenge with P. multocida. The present results suggested that prechallenge IgG and IgM concentrations in serum did not appear to be associated with resistance to P. multocida in a large-bodied turkey line and a randombred control population.

Animal Husbandry↗
PubMed1997

Lysenkoism and the population control movement.

The case of Lysenkoism in the Soviet Union helps us understand how people's wrong beliefs can be influenced by what the information they receive from outside, especially when there is a large volume of media coverage and there is no contrary information to be heard. The population control movement in contemporary United States has many parallels to the Lysenko episode.

Genetics, Population↗